A device has been proposed in the related art, which acquires road information from an external information source outside a subject vehicle of VICS (Vehicle Information and Communication System) through an optical beacon communicator in roadside equipment and an internal information source inside the subject vehicle such as map information of a navigation system and performs vehicle drive support of the subject vehicle using the corresponding information. For example, Patent Literature 1 discloses a navigation device which receives VICS information that is transmitted from a VICS center through a VICS reception unit and compares a VICS link ID in the received VICS information with a map link ID in map data recorded in an HDD with reference to information that indicates a corresponding relationship between a pre-stored VICS link ID and the map link ID. This navigation device specifies a mesh that includes a VICS link ID for which the corresponding map link ID does not exist from the result of this comparison, downloads updated map data of the mesh from an updated map data transfer center to the navigation device, and partially updates the map data recorded in the HDD.